Mandrel.



H. E. PORTER.

MANDREL.

APPLICATION FILED JULY H.19I8.

Patented M a-1*. 4,1919.

a SHEETS-SHEET 1.

H. E. PORTER.

MANDREL.

APPLICATION FILED JULY 11.1918.

Patented Mar. 4,1919.

3 SHEETS-SHEET 2- H. E. PORTER.

MANDREL.

APPLICATION FILED JULY H. 1918.

1 ,295,924. Patented Mar; 4, 1919.

3 SHEETS-SHEET 3- llllll 35 Z 'L .I 32

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Specification of'lettcrs Patent. I I

Application am m 11, 1918. Serial no. Manse.

To all whom it may concern:

Be it lmown that I, HAROLD E. Ponrnn, a citizen of the United States,residing atBayside, New York, have invented certainnew and usefulImprovementsin -Mandrels, of

which the following is a full, clear, and exparts thereof andfacilitating and rendering safe the manipulation thereof. As willhereinafter appear, the invention consists in various improvementswhich, though related in a generic sense, are capable of embodiment indifferent types of mandrels. In order to illustrate a reasonable numberof different embodiments without undue multi-- plicity of views andrepetition of illustrations I have omitted certain of the novel 1features in certain of the views. It should be borne in mind thereforethat the novel features in each form may be embodied in other forms ofmandrels, some of which are illustrated in the other figures.

Referring to the drawings which illustrate what I now consider thepreferred forms of my invention:

Figure 1 is a central section elevation of one form of mandrel.

Fig. 2 ,is a section on the line 22 of is a section on the line 3-3 ofFig. 5.

Fig. 7 is a view similar to Fig. 6, omit ting the attaching base andillustrating the parts in a different position.

Referring to Figs. 1, 2- and 3 it will be seen that I have shown a bodyportion 1 provided with an integral base or attaching member 2 forsecuring the mandrel to the face plate of a lathe or other machine. Aplurality of cams, 3 may be formed on said .the opposite. direction the.fiange for' this purpose.

edon said body portion. The sleeve 7 is provided with slots 8 in which aplurality of jaws or gripping members 9 are mounted in.- a position tobe engaged by the cams 3. In order to prevent the said gripping membersfrom dropping outI provide an' integral lug 10 on each end of each ofthem. Recesses 11 are provided in said sleeve to receive said lugs 10.The above mentioned parts may be held in assembled position by an endplate or disk 12 secured to the body portion 1 by means of a bolt 13, ina position to engage the sleeve 7.

The mandrel, thus far described may be assembled as follows: The base 2is secured to the face plate of a lathe or other machine. The grippingmembers are then inserted into the slots 8 of the sleeve 7, the latteris slipped over the body portion, 1 into engage: ment with the shoulder6 and the end plate 12 bolted-in position. The'gripping members 9 maynow be projected to grip the work by causing relative rotation of themembers 1 and 7 in one direction, thereby causing the cams 3 to thrustsaid gripping members 9 radially outward. By causing relative rotationof said members 1 and 7 in jawsor gripping members are released.

The means for efiecting relative rotation of members 1 and 7 may assumevarious forms. Thus in Fi 2 the sleeve 7 is shown provided with a ange14 which may be gripped and rotated b a spanner wrench or other tool,notches 15 i provided in said referably, however, I provide a hand-wheel16, secured to said sleeve by a driving, fit (see Fig. 13 to effectrotation of the latter. It shoul be noted that the hand-wheel 16 isdished some- .what and extends partially over the base 2 Patented Mar.a, rare.

. type of expanding mandrel, 2'. 0. one of the centering type. he parts1, 2, 7, 9 and 16 correspond to the parts 1, 2, 7,9 and 16 of Fig. 1 inboth structure and operation and need no further description. The bodyportion 1 has an integral extension 20 provided with a roller 21 at itsfree on to engage the work, thereby permitting the latter to rotatefreely when the jaws or gripping members 9 are being projected orretracted. The roller 21 is rotata ly but nonslidably held between ashoulder 22, on said extension 20, and a disk 23 having a threaded shank24 which screwsinto the end of said extension. The sleeve 7 in Fig. 4 isshown held against its shoulder 6 by means of a collar 25 detachablysecured to the extension 20 by a set screw 26 adapted to seat in adepression in said extension. I

It will be noted that instead of securing the hand-wheel 16 to thesleeve 7 by a driving fit, as shown in Fig. 1, I have shown the formerkeyed to said sleeve 7 at 28.

' While all of the forms of the inventions thus far "described comprisemeans for projecting the jaws or gripping members and means forpreventing the latter from dropping out of the mandrel, they lack meansfor positively retracting the jaws. In Figs. 5 to 7 I have illustratedone form of mandrel in which all of the above mentioned functions areaccomplished. I

As in the other forms, the mandrel illustrated in the last mentionedfigures comprises a body portion 30 having an attached on said bodyportion and held against axial movement by means of a shoulder 33, whichit abuts at one end, and a plate 34 which engages the other end thereof.By providing the plate 34 with a central opent1on 30, the latter may beprovided with a centering hole 37 at its free end as well as at itsattaching end. The plate 34 is de- 'tachably secured to the body portion30 by means of a plurality of bolts 38'.

Th1s form of mandrel comprises also aout more specifically-hereinafterthese shoulders perform an additional and very important function. v

The aws or gripping members 39 together with theoperating means therefordifler in structure from those illustrated in the preceding figures,being of the toggle type, and may e, constructed as follows. The bodyportion 30 is provided with a base 31. A sleeve 32 is rotatably mount-'mg 35, to receive aboss 36 on the body poraxis of the body portion 30,together with the latter, but are capable of oscillation with respect tosaid body portion about the axes 43, which may be termed the axes ofoscillation.

The outer surfaces of the jaws, 39 are cylindrical and coaxial with eachother and with the body portion when said jaws are in the retractedposition as illustrated in Fig. 7. j The shoulders 40, above mentioned,are also cylindrical but have their axes at 43 and are of such a radiusthat they engage the inner surface of the sleeve 32 tangentially at alltimes.

.By virtue of the shoulders 40, and the cooperatin structure, the jaws39 are projected radia y outward beyond the surface of the sleeve 32when the latter is rotated in a clockwise direction with respect to thebody position. Furthermore the extent of projection depends on theangular distance of relative rotation of said body pprtion and sleeve,the limit of projection trated in Fig. 6. In order to grip the work itis therefore only necessary to place the latter on the mandrel and torotate the .sleeve 32. Although the remote or outermost edgesof the jaws39, and the corresponding axes 43 he on the same radii of the bodyportion in the (position illustrated in Fig. 6 it will be note of linein Fig. 7 so that a toggle action takes place in pro ecting the jaws.

eing 1llusthat they are out When the jaws are in projected ositions andit is desired to retract them t e sleeve 32 should be rotated in acounter-clockwise direction with respect to the bod portion 30. Due tothe engagement of t e shoulders 40 and the inner surface of the sleeve32 said jaws will be positively moved to retracted position (see Fig. 7)on such rota"- tion.

While a hand-wheel may be provided on the sleeve 32-for rotating thelatter it have illustrated notches 51, ina flange 50 on said sleeve,into which a spanner wrench or other tool may be inserted 'to turn saidsleeve. The front edges of the'grippin members 9 are preferably beveledat 44 to acilitate assem ling of certain kinds of work.

lit is to lee-understood from the foregoing that I do not limit myselfto the specific modifications and details of construction illustratedand described, as many depar-" tures may be made in points of detail andcams an naeaeaa other modifications resorted to without do viating fromthe true spirit and scope of my invention as set forth in the claims.

What I claim is:-

1. An expanding mandrel comprising a body portion, a p urality of camson said body portion, grippin means carried by said bod 'POI'tlOD. anoperable by said d a cylindrical extension on said body portion of aradius equal to the minimum radius of said body portion.

2. As an article of manufacture, a member having integrally formedperipheral cams,

. drical extension of a radius equal to the distance from the axisofsaid member to the the longitudinal elements of which are parallel tothe axis of said member, and a cylinclosest elements of said cams.

3. An expanding mandrel comprising a body portion having a plurality ofcams thereon, gripping means, a cylindrical extension, on said bodyportion, of the same radius as the minimum radius ofthe latter and meanscomprising a sleeve rotatably mounted on said extension and body ortionfor causing said cams to project said gripping means. r

4. A chuck comprising a body portion, a base on said body portion,grippin' means supported by said body ortion an means comprising ahand-whee surrounding said base, for moving said means into grippingposition.

5. An expandin body portion, a p urality of cams on said body portion,gripping means carried by said body portion and operable by said cams, acylindrical extension on said body portion of a radius equal to theminimum radius of saidbody portion, a securin flange on said bodyportion, a sleeve rotata 1y mounted on said body portion and in whichsaid grip:

ping means are radially movable, and a hand wheel secured to said sleeveand surrounding said flange.

In testimony whereof I affix my signature.

- OLD E. PORTER.

mandrel comprising a

